Handover reestablishment method of communication system

Abstract

A handover reestablishment method capable of effectively re-accessing the serving base station when the mobile terminal fails ranging while moving to the target cell and performs ranging through the handover process, or when the direction of the mobile terminal is changed and thus, the mobile terminal enters into the serving area, is provided. The method includes receiving a handover request message from the mobile terminal; waiting without canceling a connection to the mobile terminal when receiving the handover request message; and performing a reconnection with the mobile terminal when receiving a handover reconnection message from the mobile terminal.

1 . A method for reestablishing a handover with a handover-performing mobile terminal in a serving base station when the mobile terminal fails to perform the handover with a target base station, the method comprising: 
 receiving a handover request message from the mobile terminal;    waiting without canceling a connection to the mobile terminal when receiving the handover request message; and    performing a reconnection with the mobile terminal when receiving a handover reconnection message from the mobile terminal.    
   
   
       2 . The method of  claim 1 , wherein the serving base station performs real-time reconnection with the mobile terminal without any additional signaling process.  
   
   
       3 . The method of  claim 1 , wherein the reconnection step includes receiving the handover reconnection message from the mobile terminal, and 
 reconnecting with the mobile terminal while the serving base station having received the handover reconnection message is waiting for the connection cancellation.    
   
   
       4 . The method of  claim 1 , wherein the serving base station performs the reconnection with the mobile terminal using a parameter included in the handover instruction message.  
   
   
       5 . The method of  claim 4 , wherein the handover instruction message includes a reconnect parameter.  
   
   
       6 . A method for reestablishing a handover with a handover-performing mobile terminal in a serving base station, the method comprising: 
 receiving a handover request message from the mobile terminal;    waiting without canceling connection to the mobile terminal when receiving the handover request message;    receiving a backbone message including a ranging result from the target base station which performed a ranging process with the mobile terminal; and,    reconnecting with the mobile terminal when receiving a handover reconnection message from the mobile terminal.    
   
   
       7 . The method of  claim 6 , wherein the receiving of the backbone message comprises canceling the connection to the mobile terminal when the ranging result of the backbone message is a success.  
   
   
       8 . The method of  claim 6 , wherein receiving the backbone message includes maintaining a state for waiting the connection cancellation when the ranging result of the backbone message is a failure.  
   
   
       9 . The method of  claim 6 , further comprising canceling the connection to the mobile terminal when receiving no message for the ranging result from the target base station.  
   
   
       10 . The method of  claim 6 , further comprising canceling the connection to the mobile terminal when receiving no message for the reconnection from the mobile terminal.  
   
   
       11 . The method of  claim 6 , wherein the serving base station performs real-time reconnection with the mobile terminal without any additional signaling process.  
   
   
       12 . The method of  claim 6 , wherein performing the reconnection comprises receiving the handover reestablishment message from the mobile terminal, and reconnecting with the mobile terminal while the serving base station having received the handover reconnection message is waiting for the connection cancellation.  
   
   
       13 . The method of  claim 6 , wherein the serving base station performs the reconnection with the mobile terminal using a parameter included in the handover instruction message.